package domain

import (
	"database/sql/driver"
	"encoding/json"
	"fmt"
	"strconv"
	"strings"
	"time"
)

type Duration struct {
	time.Duration
}

func (d Duration) MarshalJSON() ([]byte, error) {
	return json.Marshal(d.Duration.String())
}

func (d *Duration) UnmarshalJSON(b []byte) error {
	var s string
	if err := json.Unmarshal(b, &s); err != nil {
		return err
	}

	duration, err := time.ParseDuration(s)
	if err != nil {
		return err
	}

	d.Duration = duration
	return nil
}

func (d Duration) Value() (driver.Value, error) {
	// Store as a PostgreSQL-compatible interval string
	return d.Duration.String(), nil
}

func (d *Duration) Scan(value interface{}) error {
	if value == nil {
		d.Duration = 0
		return nil
	}

	switch v := value.(type) {
	case int64:
		// Handle legacy nanosecond values that were incorrectly stored
		// If the value is extremely large (likely nanoseconds), convert it
		if v > 1000000000000 { // More than 16 minutes in nanoseconds, likely a nanosecond value
			d.Duration = time.Duration(v)
		} else {
			// Assume it's seconds for smaller values
			d.Duration = time.Duration(v) * time.Second
		}
	case string:
		duration, err := time.ParseDuration(v)
		if err != nil {
			return fmt.Errorf("cannot parse duration string: %s", v)
		}
		d.Duration = duration
	case []uint8:
		// Handle PostgreSQL interval format
		intervalStr := string(v)

		// Try parsing as Go duration first (for newer records)
		if duration, err := time.ParseDuration(intervalStr); err == nil {
			d.Duration = duration
			return nil
		}

		// Handle PostgreSQL interval formats like "00:00:30" or "8333333:20:00"
		if strings.Contains(intervalStr, ":") {
			parts := strings.Split(intervalStr, ":")
			if len(parts) >= 2 {
				var hours, minutes, seconds float64
				var err error

				switch len(parts) {
				case 2: // MM:SS
					minutes, err = strconv.ParseFloat(parts[0], 64)
					if err != nil {
						return fmt.Errorf("cannot parse minutes from interval: %s", intervalStr)
					}
					seconds, err = strconv.ParseFloat(parts[1], 64)
					if err != nil {
						return fmt.Errorf("cannot parse seconds from interval: %s", intervalStr)
					}
				case 3: // HH:MM:SS
					hours, err = strconv.ParseFloat(parts[0], 64)
					if err != nil {
						return fmt.Errorf("cannot parse hours from interval: %s", intervalStr)
					}
					minutes, err = strconv.ParseFloat(parts[1], 64)
					if err != nil {
						return fmt.Errorf("cannot parse minutes from interval: %s", intervalStr)
					}
					seconds, err = strconv.ParseFloat(parts[2], 64)
					if err != nil {
						return fmt.Errorf("cannot parse seconds from interval: %s", intervalStr)
					}
				default:
					return fmt.Errorf("unsupported interval format: %s", intervalStr)
				}

				// Convert to duration
				totalSeconds := hours*3600 + minutes*60 + seconds
				d.Duration = time.Duration(totalSeconds * float64(time.Second))
				return nil
			}
		}

		// Handle PostgreSQL interval format like "30 seconds", "1 minute", etc.
		if strings.Contains(intervalStr, " ") {
			// Try to parse common PostgreSQL interval formats
			intervalStr = strings.TrimSpace(intervalStr)
			
			// Replace PostgreSQL interval keywords with Go duration format
			intervalStr = strings.ReplaceAll(intervalStr, " seconds", "s")
			intervalStr = strings.ReplaceAll(intervalStr, " second", "s")
			intervalStr = strings.ReplaceAll(intervalStr, " minutes", "m")
			intervalStr = strings.ReplaceAll(intervalStr, " minute", "m")
			intervalStr = strings.ReplaceAll(intervalStr, " hours", "h")
			intervalStr = strings.ReplaceAll(intervalStr, " hour", "h")
			
			if duration, err := time.ParseDuration(intervalStr); err == nil {
				d.Duration = duration
				return nil
			}
		}

		return fmt.Errorf("cannot parse PostgreSQL interval format: %s", intervalStr)
	default:
		return fmt.Errorf("cannot scan %T into Duration", value)
	}

	return nil
}

func ParseDuration(s string) (Duration, error) {
	if s == "" {
		return Duration{}, fmt.Errorf("empty duration string")
	}

	s = strings.TrimSpace(s)

	duration, err := time.ParseDuration(s)
	if err != nil {
		return Duration{}, fmt.Errorf("failed to parse duration '%s': %v", s, err)
	}

	return Duration{Duration: duration}, nil
}

func (d Duration) String() string {
	return d.Duration.String()
}

func (d Duration) Seconds() float64 {
	return d.Duration.Seconds()
}

func (d Duration) Minutes() float64 {
	return d.Duration.Minutes()
}

func (d Duration) Hours() float64 {
	return d.Duration.Hours()
}